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4.62.164.66
So to carry on from the thread below, the picture here shows a really classic 'stacked ply' plinth for the really classic Garrard 301.Since I'm in the process of implementing one, I won't try and suggest why they are the odds-on winners for most 301 plinth designs, but I'll assert that they are, in 99% of all new restorations, the plinth of choice . The Japanese, the Euro and the American aficionados seem to agree overall ---- MONDO LAYERED HARDWOOD PLY plinths rule the landscape.
Is it urban myth ?
Is it to deaden the sound of motor and idler-on-platter-rim ?
Or is it better to channel the unwanted clatter out and away via a more vibe-conductive material ?If you go with the ply concept, should you align horizontally, as above, or try a vertical alignment, wherein the edge of the ply forms the top deck ?
Should the dead-end-labyrinth effect be emphasized -- ala more layering leading to more tortuous return-paths ?
Is there something integral to the Big Torque Idler Drive that requires a major vibration sink that converts and buries versus a quick-transfer resonance exchanger medium that sends the same set of resonances down and away into the rack, wall, flooring, etc.
Thoughts ?
J.
Follow Ups:
Dear JDI was thinking of buying an Ikea Lack Table, cut-out the top and fit the Lenco straight on.
It is a cheap option, any comments on the chances of it sounding good?
Cheers
Hi Kisall the idler wheel tables i have used liked heavy mass plinths.
no experience with Lenco.. but i have a done a number of experiments
on 301/401/td124/sp10/rek-o-kut/rca/denon.... here is a summary.the easist way to get good sound is layered birch plywood. birch ply is close to neutral. mass matters.
30 lb plinths are not as good as 70 lb plinths. and 70 lbs units
are not as good as 100 lb units... the differences in sound quality
are not subtle. the limitation to the weight of the plinth is the stand. the stand should be 2-5 times wt. of plinth and the the ht of
stand should be at least 75% less than width of stand. heavy mass
stands directly coupled to floor seem to work best.avoid the following: 1) all layers or chipboard; 2) all layers of mdf... both
these combinatiosn give dead sound.. the chipboard is worse than mdf( more muddy)the 1st layer (clostest to the motor board is the most important). this can be made of some other material other than birch ply to color-compensate for the natural sound of the table. both the 301&401 are a little bit dark ---
using a maple 1st layer helps brighten the sound a bit ( a single 1/2" layer of mdf can be used also).note that the loricraft style plinths give acceptably good sound
that is remarkable considering the light weight. but the unsuspended
heavy mass plinths are significanty better than loricraft plinths ASSUMING a proper stand is used.rgds
munna
Hi munna,Great list of compiled tips, thanks for putting that together.
Tell me more on this one ::
the limitation to the weight of the plinth is the stand. the stand should be 2-5 times wt. of plinth
So...... This is because a top-heavy (light stand w/ heavy plinth) arrangement here would induce some variation of 'wobble' ?
Just wondering.Also, any view on hardware / fixing bolts for the 301 ? What's your call on what goes in the 'washer' recess of the fixing bolts ?
( Neither are an issue, but since you mention the 'livelier' maple first layer, I wondered about the length, type, composition, etc having an effect on things.... )And while we're on tiny topics, what's your view on footers --- spikes, rollerblocks ? Materials ?
Thanks again,
J.D.
HI J.Dplinth shape... may make a difference ... same weight plinth in
27" long plinth seems to sound better than in 22" long plinth. i think because of stabilty.. width may need to be about 2/3 height.stand height ... just common sense to make the heavy thing more
stable... i think souund quality will suffer audibly if rack can
be made be perfectly level without shimmying.footers... i have tried about 4-5 types of cones (varying size from 1" to 2" and material from wood to brass to aluminium). i dont
hear much difference when plinth is about 100 pds. so frankly the
$4 brass cones from Madisound maybe the sensible choice. also
going from rubber feet to conepoint on 50-pd chipboard plinth made some difference...
but cone to rubber feet on 100-pd ply plinth made very little difference. i think the key is mass.. heavier the plinth, the less
everything else matters.bolting... unfortunately, have not played with this that much. but
it has always vexed me. i try to use the smallest softest aluminium
washers. i try to avoid rubber.. but have not really compared
mounting schemes too much.. i focused more on size/shape/material composition of plinth. but comparing 301 & 401 bolting schemes
.. 301 has 4 holes will means 4 bolt from to top to heavy plinth.
401 has needs to be bolted from bottom with 4 not so big bolts. this
means that the 401 has to be bolted to a board which then needs
to be bolted to another board.. this means 2 layers of bolting is requirted. frankly, i can hear the hear difference between 301 & 401
but the difference between the 2 bolting schemes is hard to detect.
needless to say i much prefer the 301 bolting scheme but wish i could try bolting with
8-12 holes instead of 4. my friend seems to think 3 very heavy
bolts is audibly better. i think here again, the heavier the less
significan the bolting scheme.
material.. .. as mentioned earlier they make a big difference. i want to compare the following: 1)layered birch ply; 2)layered solid wood (cherry/maple, etc) 3) layers of different materialrgds
munna
Although people on this forum and in the hi-fi industry in general would like you to believe that the jury is still out on how to obtain the best performance from a turntable, the research in the industrial fields concerned with vibration control was done years ago, the industry has settled on accepted designs, and their experiments explore domains 100,000 times smaller than the smallest feature on a record surface.For specific pointers, take a look at what the industry uses for Atomic Force Microscopes: the plinths are either honeycomb steel breadboards (although they can be individually tuned for particular frequencies) or granite slabs, with tapped holes so your device can be securely attached to it in order to eliminate the generation of secondary vibrations (compare this with all the specialty support boards in hi-fi where they rely on secondary vibrations to achieve their unique "sound"). FWIW, turntables operate on the same physical principle as AFMs -- turntables are just a very-low-resolution, high-data-rate AFM.
It's always more comforting to believe that the experts in these fields don't know more than you do, and by just tinkering around in your garage you'll kickstart the next revolution in physics. Comforting, but not true. Then again, implementing the industrial experience to hi-fi would only produce a great performing turntable, not one that necessarily "sounds good", and thus the number of manufacturers would dwindle to single digits... not something that the hi-fi industry is looking forward to, hence the current sorry state of affairs.
John
Except that no scientific instrument manufacturer woould stay in business with products which had the degree of performance degradation inherent in the way turntables are built, the Garrard included.I would like to be able to say that no Hi Fi manufacturer would stay in business with scientific instrument pricing, but.....
What I mean to say is that unless a turntable is built to instrument standards (and if anyone has I haven't seen it) then the decoupling solutions applicable to instrumentation are probably not going to be the entire answer because they don't address the problems of internally generated vibration.
While I've got you John, can you tell me if there is a simple rule of thumb for the ratio between the minimum speed which gives adequate lift and the maximum sustainable speed for a hydrodynamic bearing?
Non est ars quae ad effectum casu venit - Seneca.
"That which achieves its effect by chance is not art"Mark Kelly
> I would like to be able to say that no Hi Fi manufacturer would
> stay in business with scientific instrument pricing, but........but the audio manufacturers have outdone themselves offering ludicrous engineering at stratospheric prices.
> What I mean to say is that unless a turntable is built to
> instrument standards then the decoupling solutions applicable
> to instrumentation are probably not going to be the entire answer
> because they don't address the problems of internally generated vibration.I don't agree with this; AFMs use translating and rotating stages, so they encounter the same internally generating noise. Certainly, the vibrations produced by these stages are a lot lower in amplitude than the ones generated by a 33rpm spinning platter, but then again an AFM needs to have a resolution 5 orders of magnitude higher than what turntables need.
There simply is no engineering reason for the sub-standard products audio manufacturers promote -- it's just ignorance and the entrenched dynamics of a niche, uninformed, segment of the market.
> While I've got you John, can you tell me if there is a simple rule
> of thumb for the ratio between the minimum speed which gives
> adequate lift and the maximum sustainable speed for a hydrodynamic bearing?I'm not qualified enough to offer a definitive answer, but from what I've seen the details of the design are critically important, thus precluding a simple rule of thumb. I've asked some of the experts around here, and they've told me that for such low rpm applications (33 or 45), air bearings would be my best option, although most of them thought that a well designed sleeve bearing could work very well.
John
For certain there are lots of ideas around about plinths and there's no real quarrel with thinkiing about it and trying it and listening to it and rethinking it and re-trying it ..... but ::To re-phrase the question, there is one specific-recipe plinth, for idler-drives in general, which is comprised of :
* Stacked high-grade plywood, usually birch, necessarily high mass.
* Each ply layer clamped and simple-wood-glued in place.
* Internal cut-outs designed to closely surround mechansism, without touching.
* Turntable mechanism fastened securely, minus springs / compliant elements.This recipe is the one that seems to be the worldwide solution to taming the Garrards, Lencos, Rek-Os and even the older Thorens tables.
My question isn't whether I should add sorbothane or Mdf or drywall to this existing recipe, but:
* Can anyone posit the general "why" of this specific plinth recipe ? Are we guiding the motor & bearing resonances out and away, or running them around in circles until they're exhausted ?* Is there any consensus on directionality (vert or horiz layering) or actual number of layers ---ie, more thin plys versus fewer thick plys-- ?
Regarding all the "try it and listen and judge for yourself" tips, well, I'm on the third try now. I'm already doing that now. I've done a simple-frame plinth, a chiselled-out plinth and now I'm trying to get at the prevailing wisdom plinth ... which is the stacked-glued-birch-ply version.
What do you think is the principle of this one ?
Thnx,
J.
Hi Jim,I was going to stay out of this thread, however, since you are thinking of making a birch ply stacked plinth, I would like to add a few points.
The Martin Bastin Plinth is made from about 6 layers of birch plywood - I could give more accurate data if you needed. This is considered to be an excellent plinth amongst Garrard aficionados in the UK. I have one, and I can confirm that it cleans up the somewhat soggy sound of the Garrard, though I am still tinkering with two turntables, so an accurate comparison of the plinths is difficult.
The layers of plywood are glued and bolted together with this plinth, I can’t say if glue alone would work.
I have a contact who might supply plans for a stacked plinth according to the Martin Bastin design.
The Martin Bastin plinth does not eliminate motor noise; I have tried my noisy 301 in three different plinths and the results were more or less the same in all three. I don’t think that any type of plinth would silence this particular turntable. The problem is that the motor is coupled to the platter via the idler wheel, so a noisy motor will result in a noisy turntable. The theories postulated by the ‘experts’ below, that a massive plinth will absorb the motor vibrations are simply not correct on this point.
If you have a somewhat noisy 301 (and remember the noisiness of the motor varies from one model to another) then I think you will either have to accept a certain degree of low level noise as part and parcel of the Garrard experience, or hold out for Mark Kelly’s motor upgrade!
Best regards,
BK
I'm currently waiting on parts from the bearing supplier and the laser cutter (for the mount to adapt the 301 for the new motor) and hoping to be up in the next couple of weeks.I finally got around to fixing the spectrum analyser (HP3580A) so I will be able to quantify vibrational output. I'm not sure whether I'll have to build a three axis accelerometer or just go with piezo bimorphs.
Non est ars quae ad effectum casu venit - Seneca.
"That which achieves its effect by chance is not art"Mark Kelly
I had an idea to buy a Teres motor, and to mount it outside my Garrard turntable so that I would have the option of driving the platter via a belt or the idler wheel.It would be interesting to discover if the sound of the Garrard is really down to the idler drive.
Another, more off-the-wall idea Iwas that if a pair magnets were fixed on top of the motor spindle, then induced Eddy currents on the platter would cause it to spin.
This approach would very effectively de-couple the motor from the platter, however, the high torque would be lost, and I have no idea what speed the platter would settle at.
Here is a useful motor resource
http://www.myhurst.com/hurstmfg/products.jsp?image=3&product=0
BK
Hmm. I really can't see that that will work but then I've never tried it. As far as I can see if you get any motive power at all it would have an extremely soft speed / torque characteristic which translates to poor speed stability. I think the lesson to be learnt from the Garrard experience is that motor decoupling is a furphy foisted on us by the proponents of belt drive.I have built several magnetically coupled drives and they are harder to get right than they look. If you like I can run one of my NdFeB magnet drives on the Garrard platter to see if there's any drive.
Non est ars quae ad effectum casu venit - Seneca.
"That which achieves its effect by chance is not art"Mark Kelly
Hi BK," The problem is that the motor is coupled to the platter via the idler wheel "
While the temptation exists to try and think around this, you're completely right. But the only defense against that particular venue is the record mat, really.
It stands to reason though, that top-deck originating vibration, even if not primary, would be partially dissipated via the ply-stack.At this point in my project, I'm listening everyday to the chiselled-out fir plinth and yeah, there's background noise. Not buzzy like a 60hz bleed, or pounding / thrumming like rotor vibration, but a little more like, well, a vague 'groove rush', or very soft tube noise, really....
The thing is I don't really know if my table is 'noisy' one or not. Of course it's noisier than the beltdrive Vpi Aries, which is some kind of stealth-bomber silent re motor noise.
But the Garrard is a long way ahead in speed stable timing, drive, and pace. Given a little slack in either of these two arenas, I think I'll take a little bland background dither before any kind of speed-anything at all.
My all-things-considered overview of turntable matters comes to :::
* Nobody / nothing is perfect so you'll never find a "10 of a possible 10" system
** Often the only real art of the table designer is in his/her ability to misdirect your attentions from the arena where he knows he's a little lacking
*** Since there will be a zone of imperfection, the higher the score on the built-in "ignorability" re that zone, the higher the overall honorsHow that takes place is very different on different designs.
As re Mr. Kelly's motor upgrade, I can't even begin to understand reading about it let alone afford it.....
Cheers,
J.
If all you get when playing unmodulated grooves at high volumes is general background white noise, then I think you are in the zone.The high noise floor of the Garrard is sometimes just above the background groove noise level. The test which shows this up is to play umnodulated grooves at high volumes and to switch the motor on and off and to compare the background noise in each case. With one of my turntables, and with the motor on, the noise level is higher. The noise is a mixture of hum and rumble at a very low level. It is sufficiently low to not be intrusive when playing music at normal levels, but it is there nonetheless.
Best regards,
BK
What follows is my opinion only (just so I don't have to keep typing "I think" or "I feel").The most important vibration modes are those where the vibration can cause relative motion between styls and groove. Assuming stereo operation, lateral vibration will be picked up as noise, longitudinal as speed variation and vertical as difference between channels. For most of the noise produced by a turntable this last is relatively unimportant.
It is therefore best to couple the deck to the plinth in such a way that the relative motion produced by the two horizontal modes is minimised. The key to this is consistent propagation velocity. The propagation velocities of the materials in the Garrard itself are clustered between 4000 and 5000 m/s so the ideal material will have a velocity in this range.
Plywood is relatively isotropic in the plane of the laminae for the simple reason that it has two average grain directions not one. Across the plane of the laminae the story is very different - the modulus of elasticity is less than a third, so the propagation velocity is nearly halved. Birch ply has a propagation velocity around 4200 m/s in the plane of the laminae so it works very well with the plane of the laminae parallel to the plane of the turntable deck.
Non est ars quae ad effectum casu venit - Seneca.
"That which achieves its effect by chance is not art"Mark Kelly
Interesting, mark. That didn't saturate my razor-thin cortex until I read it again, but I think you may have a point or two.First, what exactly do you mean by longitudinal -- ? Something along the lines of "roll"...? I'm not clear on that....
But your overall point about horizontal modes and ply directionality makes total sense.
Supposing, for just a moment, that I knew an independent EU furniture maker whose plant produces laminate woods in all kinds of thicknesses & curvatures, as well as flat. I was only today quizzing him on how their hydro + microwave contouring process works. Essentially this guy's capable of making me a block of custom, high-compression name-your-woods laminate....
What if any, advantage would that be in the construction of an ultimate stacked-ply plinth, or would I be wasting his time reinventing the (birch ply) wheel ?
Oh, and I'm thinking your 'horiz. mode' emphasis is confirmed by Jon Noble's use of those diy Aurios , or Rollerblocks or whatever they are, which he claims to have put him way ahead in his 401 tweakage... I'm pretty sure those are mostly effective in the horizontal mode.
Whaddya think of a factory pressed laminate ? Crazy ? It would look cool in the extreme ...
JD
By longitudinal I mean tangential to the groove at the stylus, lateral and vertical are at 90 degrees to this and to each other. There is no need to stick to this frame of reference but it makes life easier if you do.I think the laminates idea has merit. I am basically investigating doing more or less that with slices of cherry and / or various eucalypts but as I lack access to the high pressure laminator I am going to do it the way I do my carbon fibre structures (which are mostly laminates), vacuum bagging epoxy.
Non est ars quae ad effectum casu venit - Seneca.
"That which achieves its effect by chance is not art"Mark Kelly
Well, with respect to the second question, I don¡¦t know of anyone who has done one ¡§vertically¡¨. If they have, they have not reported it to my knowledge and I¡¦ve looked in many places. Perhaps folks at Shindo and others who have done much of the early Garrard work and who use the ¡§world-wide accepted methods¡¨ have already done all the ¡§try and test¡¨ efforts that you don¡¦t want to hear about, including the ¡§vertical¡¨ approach. If someone has, I agree, it would be nice to see a write up of what ¡§doesn¡¦t work¡¨ in that regard and how ¡§horizontal¡¨ vs. ¡§vertical¡¨ efforts ¡§stack up¡¨. ƒº. At the risk of suggested you do something more than you¡¦ve already done, maybe try one vertically and see how it performs. Probably plenty of folks that would like to hear of your experience.Perhaps saying something that you already know, I was always under the impression that the dispersion of resonances caused by the high rotational speed and heavy torque in the motors of these tables was the primary reason for high-mass. The reason for plywood, in my mind, is that the structure of the wood fibers themselves and the directional diffusion afforded by the ¡¥cross-banded¡¨ ply layers absorbs resonant vibration. It addition, and with proper ¡§feet¡¨, the plinth should drain energies out and away from the table. So, I¡¦d say the answer is both of the things for which you inquire ¡V but I am no acoustical expert. The idea of constrained layer damping was offered as an extended possibility such that any one material might not result in a single resonant point being a problem ¡V recognizing that an improper mix could well do as much harm as good in that regard.
I think that Jean Nantais has addressed this issue a few times in the Audiogon thread but I haven¡¦t the energy to sift through 2000+ posts to find the reference. Perhaps post there with your Q¡¦s. Jean is very gracious to respond. Melomane may chime in on this thread, too.
Thanks for the thoughts. Sorry to give any sort of impression that I didn't want to hear about other kinds of projects or even 'what doesn't work'---- but I was trying to narrow this down to the stacked-ply-glue-only solution for garrards.Maybe it's because I'm all too easily led on idea safaris (my fault), or because I'm not sure that other tables tend to sound like a grease-301.
But of all the many many ideas out there, the stacked-ply is the one that turns up with a distinctive regularity, and in all the right places, too. By that I mean users of SET gear, fullrange high-efficiency spkrs, SPU carts, far-east audiomaniacs of a certain inclination, Mono aficionados, jazz collectors, 78 enthusiasts and, well, analog cranks everywhere. This is just a fuzzy enough science that things like 'commonly-associated-with' tend to be very telling.....
I'm only approaching my 3rd plinth experiment. I thought it might be a plus to get as much of the info on the design that I see in all those right places, at least per my own sensibility. Before going off onto roads not-as-travelled.
( A similar idea would be the idea of SME arms with 301's ---- this is all too often the arm that gets the tracking duties for many, many a 301. Rather than posting a wide and generic question, I think it would make sense to narrow it to Sme knife-ege pivot arms and go from there. If feasible, I'll try and look into that as well.)
J.
Hi JDin my experience, arm does not make a difference on heavy mass tables. i have tried
30+ arms(all types heavy, light, medium, uni-pivot etc) on my heavy mass plinths and have not yet come across an arm that had an issue with the table. each arm displayed its
own strenghts/weaknesses. i think the reason a lot of people go with sme is cost & versatility ..3012, seriesIII, and 3009 (all versions) offer sensible (performance+quality)/price ratios. another reason is that the sme 'sound' is what a lot of people are used to...it is balanced & civilized. so hearing it makes them comfortable. personally i think the modern arms offer better performance -- but require more
cartridge experientation to get honest results.
rgds
munna
...for Lenco projects, we now have some idea of what sounds good together if you are looking to go the constrained layer damping route. The very first plinth we (my son and I ) built was based on the materials as seen in the link below. Since then we've done others and the best "sounding" that we found follows the same basic process with birch ply used in place of the MDF and ISODAMP material used in place of the vinyl floor tiles. We found that the all-ply, instead of a combination of ply and MDF (but with the aluminum, sheetrock, damping material), resulted in more "life", for lack of a better term. We've used Corian in all of ours (except one) because we have a relatively cheap source. One curious thing that happened was that we found that the plinths we built without the sheetrock sounded just a tad less "dead" when drumming one's fingers on the top of the plinth when completed. The drawback is that one must use different methods for finishing the sides. Now, all of the tables for which we've built plinths sound great, including one that was ALL birch ply (with the sheets alternated for opposing grain direction). Differences are subtle between materials used, but noticeable, and maybe a matter of taste as opposed to "right" or "wrong". It is worth a try to experiment if you have the time, materials, inclination, and tools.
That is really nice woodwork. Truly one of the niceset looking plinths I've seen.
..to do, too. Here are a couple more we've done using different treatments. Well, I can only do one link, so I will do one link and you'll have to copy and paste the other. :-)http://cgim.audiogon.com/i/vs/i/f/1106588443.jpg
JD
As Mosin indicated this stuff is anything but all worked out, which I found over a a great deal of digging, Googling and researching various sites and discussing the engineering theories with a number of experts and experienced plinth builders.I have read a number of brilliantly written and very compelling explanations and articles written by folks with extensive engineering backrounds explaining their understanding of the theories of plinth construction and how it relates to controlling damping and altering resonances, the problem is that many of these writings directly contradict each other to one degree or another.
Some of this stuff seems as if some of us seemingly confuse Loudspeaker cabinet or even Violin construction design aspects with plinth design.
Some aspects are obvious as you don't want an absolutely dead 700 lb. lead plinth or a very light highly resonant plastic plith either.
And you'll see the same situation in the engineering involved in
various commercial turntables, some very highly regarded tables tout
construction with a layer or layers of Sorbothane between the layers of MDF, both the use of Sorbothane and MDF as an exclusive material
in plinths is generally considered verbotten in most prevalent schools of thought, and any number of other approaches that are counter to prevailing thought on the subject.The main benefit of the heavy dense constrained damped plinth is IMHO taming the torque impulses and inherent resonances of the reletivly large powerful motors used in Rim and Platter drives, in the words of Jean Nantais "The motor wants to move the table" ( I'm paraphrasing here)
and as these reletively large and very powerful motors are attatched to directly the top plate and not isolated by a belt,this would seem to be a very serioysly critical aspect.
Those powerful motors and their respective drive rim or platter drive systems are what give these tables their amazing speed stability, over coming the changes in pitch inherent in most belt drive tables which to one degree or another allow for some degree of stylus drag, degrading their PRAT and ultimatly musicality to whatever degree. This is easily demonstrated with a Hunt or even AQ brush, just put a little too much pressure on the brush and the reduction in platter speed is obvious in most belt drives
with a Lenco or Rek O Kut (the tables I have experience with) tables
are unaffected, these effects become glaringly apparent when use various tables as RCM's.The bottom line is by building a heavy Birch Plywood or Birch Ply/MDF layered plinth is highly beneficial to the sonic performance
or Rim and Platter drive tables.I'm kind of hedging my bets by bolting my plinth's together rather than gluing, so at some point when I and if get the urge I can substitute layers of different materials and see if I can percieve the differences (if any), or if the missing variables or whatever become Known I can incorporate the changes to make my plinths optimum.
My advice would be to just go ahead and build yourself one now based on whatever your common sense, preferences or gut feelings tell you is best, rather than waiting while attempting to determine the correct approach as you're quite likely going to end up waiting until you're too old to actually build a plinth, another bit of Jean Nantais wisdom is that this stuff is supposed to be fun, and I couldn't agree more,if it's not fun, then what's the point ?
The differences (if they even are perceptable) are VERY subtle
to say the least, but the differences with a heavy plinth with a machine like your 301 are anything but subtle.Regards FredJ
Hi again Fred, I hate to point this out, but until you glue and clamp those layers together you're still sitting on the fence and compromising the effectiveness of your plinth, and you'll reach old age without ever having actually heard what your plinth can do! Don't worry about hitting the "perfect" recipe for a plinth (besides, in CLD the differences are not that large, and I'll be damned if I'll sit around concocting different mixes and then going to a Helluva lot of trouble listening for differences: if the thing blows me away I am happy), it'll never happen, and since it will never hapen, then you'll never hear just how good whatever plinth you have is: as long as they are not securely glued together the contrained-layer-damping is moot, since they will vibrate against each other no matter how much you torque down the bolts, and will not be acting as one mass to make a CLD plinth. I demonstrated this to my own satisfaction when I compared a glued and clamped Direct Coupling plinth (in contact over a maximal surface with the metal top-plate) which was smooth and incredibly effective (ultra detailed, slamming, PRaT-ful, silent), with one in which shims were screwed into place to achieve the same thing, which resulted in various distortions and exaggerations. By wood-gluing and clamping the layers together they "speak with one voice", are a single mass in which the CLD becomes effective. Try it, damn the torpedoes, glue the thing, sand it, paint it, this part is the most fun! These days I am marbling my plinths to freeze in a moment of time the chaotic behaviour of fluids (I float alkyd paint in a tub of water and stir and dip the painted plinth in when a psychedelic pattern appears) to achieve a pseudo marbling which I then varnish, incredible fun. So better an "inferior" plinth glued together to act as a single non-vibrating non-resonant mass than a series of layers loosely held together (no matter the torque), better materials or not (they all have some penalty/signature/behaviour). Run the last few yards for a touchdown and have fun, and then move onto the next! And yes, building the plinth so it is married to the underside of the plinth pays large dividends in terms of focus, and especially utter spooky silence which even the high-end belt-drivers had never heard before from a turntable. We were many times convinced the phono input had been switched out when suddenly the music emerged from UTTER silence.
Thank you very much for letting me know !I did glue my L-88 plinth but the 2 I'm working on right now are bolted.
Well I have several bottles of wood glue taking up space and I suppose I won't have to worry about the layers sliding around
when clamped mitter der bolts ;-)Thanks again
Kind Regards Fred
Oops, sorry Fred, didn't know you had already completed a plinth. Howzit compare with your other 'tables? I see you recommending the Audio Technica 1000-series tonearms all over the place, you must like them! Now my absolutely favourite tonearm (I made a tonearm cable out of Music Boy/Petra for it), I am now getting my second one! More lucid, more detail, better bass and rhythm than modded Regas, and a removable headsell to boot, does it get any better than this?! The Music! The Music! I have to say though, that the Denon DL103 on the Rega on a Direct Coupled Lenco is about the best I've heard, period (the Denon likes the Regas better than the ATs, so far). There is a synergy between the Denon and the Regas, and between the Regas and the Lencos, and finally, especially between the Direct Coupled Lenco and the whole shebang, which ends up having the slam and rhythm of a Decca, and the finesse, smoothness and filigree detail and air of an upper-level Koetsu. If you haven't yet got yourself a Denon (vanilla-flavour), then stampede to the closest dealer poste-haste! Of course, there are other contenders, but none as "perfect" as this happy Denon (which is to say, the best of both MMs - PRaT - and MCs - speed and focus - rolled into one, with no adible tonal aberrations). Jean Hiraga an audio legend, once said the Denon was the most perfect transducer ever developed, and hearing it on the Direct Coupled Lenco with re-wired Rega, I have to agree. In fact, I am going to make a special Lenco just for this combo! Ain't these cheapie Lencos a blast?! Off to the garage to start sawing!
I don't know if you remember, but quite a while back, I was planning on getting a Graham Robin to run MC's and you suggested I try an AT 1005 mk II 1007 or 1009.
As luck would have it that very day I found an 1005 mk II on eBay UK at the extraordinary cost of $70 and shipping, I must admit I was a bit leery, but made an AT armboard for my trusty TD 125 mk I and mounted my half shot BPS on it an I was immediately blown away, the BPS sonded like a serious upgrade, I'd been using it on a Thorens arm that I'd tweaked extensively to get the BPS right, damped the armwand with different materials until I settled on Teflon tape played around weighting the headshell etc. until I thought it was as good as it was going to get.
I ended up being so impressed with the AT I wanted to make sure I
had another and ended up getting another as well as a 1009, I threw the 2nd on a stock Bogen with my Dyn.10 x 5 and it sounded superb
the arm geometry being out of spec and all.I'm with you, I love the AT 1000 series, aside from the great performance I've found them very easy to set up and live with, like so many other things in analog one wonders why some of this wonde'rful stuff ever got discontinued in the first place, or why they weren't re-introduced ? Beancounters no doubt ;-)
And I have enjoyed giving others like myself the same great advice
you gave me as most of us will likely never have the wherewithall for a $3 to $5K tonearm, same goes for the Lenco's I never imagined I'd own anything like this, I was however planning on a Walker P. for
next incarnation ;-)Funny you should ask about the DL 103, DHL will be delivering mine tomorrow :-0 I found an ad on Audiogon for the German VDH distributorvclosing out all his VDH gear, and managed to get his VDH DL-103 with less than 5 hours on it, for a little more than $400 which seemed like too good a deal to pass on, it has the same stylus VDH uses on his Frog and a Boron cantilever, apparently the VDH DL 103's retain the essential character of the original but add a bit more air and detail and has an extraordiry long lived stylus, which is very important to me as I'm kind of going into a semi retirement situation.
The still in a state of temporary analog insanity ;-) bought a Project 12 C from a Brit distributor who was taking on the line and had his demo model which he'd never got around to trying, so now my Dogs and I are living lean and mean for the forseeable future, but I couldn't resist, I'd always wanted to try a 12" arm but the seemingly irirational prices the SME 3012's fetch and the reduction in arm rigidity that I felt would offset the reduced tracking error had kept me from seriously considering one,along with the ($1,500 toll) and all the other 12" arms
are way out of my league $$$$, I got a too good to resist deal on the Project so it's going on the L-88 as the 2nd arm with the DL 103
I'm going to line the armboard slot with Mu metal foil to precluse the hum apparently a problem with 2nd arms on Lenco's I'm hoping the
greater distance will be helpful in that regard as well.
As to the Lenco sound it's truly amazing, actually kind of shocking but did actually sadden me a mite as my beloved TD 125 suddenly sounds a bit like a toy, but an inmate recently sent me the Chadwick Modification article so the TD 125 will likely not sound like a Lenco, but respectable nonetheless.
the stock Bogen with the slapped on AT 1005 pretty much smokes any table I've ever owned. The 88 hasn't been used at all to speak of beyond trying different footing strategies, etc I'm in the midst of moving, it will have to wait until I'm in my new digs
but the basement there is huge and has a workshop and storage room
directly adjacent to what will be my listening room the idea of that lessens the Bataan death March aspect of moving.Regards Fred
I know what you mean about shock and sadness: when I first heard even a cheap idler-wheel drive I KNEW it was a superior system and I was both elated and angry (why was everyone crapping on idler-wheel drives, as they did until recently ;-)?); when I first found and fixed up a Lenco (because I couldn't find any Garrard 301s/401s: before the internet) I was stunned and in Seventh Heaven. But I was living in Europe and my high-end 'tables - a Maplenoll and an Audiomeca - were at home safe. When I finally went back home and compared and heard what I already knew (that the Lenco would smoke them), I was also saddened, as I had loved both those 'tables. On the other hand, Lencos are fun as they're cheap, and also because I hear my records as I've never heard records played before, and finally the Lencos, once rebuilt and re-plinthed, require no maintenance, just flip the switch and play year after year! SUCH speed stability, slam, detail, and all naturally presented! Glad you like the A-Ts, stunning tonearms, teaches us to keep our ears and minds open, just like the Lencos! I pick up my second 1009 tomorrow, intended actually for an Ariston RD11S, which I also love (the trick is to focus on PRaT: if they have PRaT, then you can still enjoy them when living with a Lenco; if they don't, then get rid of them). My next Lenco will be permanently set up with a Rega/Denon, but just in case, it will have a removable armboard ;-).
I suppose it's the Goebells thing,repeat something enough times and it becomes the truth,I spent most of my life assuming that Belt Drive was the way ! And that the inherently noisy complicated Rim drives, Idler wheels and drive pucks and all the rest were quaint antiquated devices a couple steps up from the Gramaphone ;-)
I assumed that TD 124's and Garrard 301's and 401's etc. were just very expensive (Ludditte ;-)nostalgia toys to run SPU's and such.When I unboxed my first Lenco, a well used L 75, it took me about 10 minutes to realize what an elegant and downright brilliant mechanism it was, although it was quite noisy (I hadn't loosened the transport screws (DOH)after that was rectified it became essentially silent after replacing the Idler wheel spring with a substantial rubber band, dissasembling the motor, cleaning it and relubing the bushings and cleaning up the rubber on the wheel with alcohol and rubber dope it was dead silent, I used it as an RCM for a month or two and became seriously impressed by the steady stable power.
That and the AT 1000 arm's have altered the way I look at these things, which lead me to take a chance on some very cheap old Rek O Kut 34's which are no Lenco's as far as rumble but really nice for what they are and tuned up even stronger than a Lenco, the ultimate RCM. I'm just finishing a Plinth for one, I'm going to try an Acos
arm with an X3 Ortofon on it, lot's of fun !I'm very suprized Lenco's and the other branded Lenco mfg.heavy platter PD tables are still as reasonable as they are ??
A couple of weeks ago I happened upon a Goldring L-59 the heading was poorly worded appearing as if it was just a wood case for an L-59 apprently most folks don't bother to look at the actual items because, I was shocked when only 3 others bid and I got it for $ 32.00, I'd completely forgotten about it, I actually felt a little guilty I have become a shamless lenco hoarder ;-)
Regards Fred
Well, Lencos have only generally been accepted as good only very recently, with my internet campaign to have them and idler-wheels in general more widely accepted, a campaign which started only a little over a year ago on Audiogon and this forum (and a few others, with many nasty battles....fun!). Now Lencos are recognized (only partially though as the majority still won't believe it), they have two problems: 1) they are too cheap so the status-seekers still avoid them, thus keeping the prices down; and 2) they are much simpler/more elegant that the big Garrards, which by their very complexity and battleship build quality (which doesn't mean they are better sonically or even in terms of engineering design than the Lencos however) have a larger "romance" factor, all those gears and levers are very Baroque/Rococco and thus fascinating (the Mad Genius Factor), something which I can actually respect (I had an NOS Garrard 401 in my hands).I have a Rek-o-Kut Rondine which I will soon be working on, it is even more massively built than the big Garrards, and it is absolutely drop-dead Art Deco gorgeous (with Art Deco lettering and a facetted pilot light dead center, with a main bearing you could beat a bear to death with), and I have bought an ESL tonearm (made by Ortofon) which is also Art Deco and seems to have excellent bearings and is very well constructed. Maybe another unrecognized star! But having heard the Utter Perfection of the Direct Coupled Lenco/Rega/Denon DL103, I have to make myself one (the last was for a friend) first! So many idler-wheel drives, so little time!
Just to sort of reiterate what John said, when I first screwed my Russco into its plinth, the chassis still rang slightly when I rapped it with my knuckle, so I went to the hardware store and bought some weatherstripping (you can see some of it poking out from the side in the photo). I really had to wrench the screws down, but the result was that there was 360 degree coupling between chassis and plinth, and when you rap it there is a dull thud.BTW I used what my local lumber yard calls 3/4" cabinet-grade birch-veneer plywood. It's really good stuff to work with.
It still takes me aback how quiet this table is, given the size of the motor.
1) No one has this plinth stuff down pat. FredJ reminded me of that recently, and he is right.2) Who knows what is real and what is myth? See #1.
3) Get more turntables, so you can try different ideas. ;)
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